@ Asassin - I agree with you 100%
It's funny because I made this same point and argument about SSD's (in defense of OCZ and against the propagandized Crucial Bias) a year ago and battled with you on many occasions. I felt exactly how you do about that issue, and my feelings are the same on mechanical HDD's.
I believe there is simply too much variety and quick paced MFG change on modern PC hardware to allow the consumer with such limited sample size to accurately predict or assess product reliability in any meaningful accurate way. The reality is you could buy the worst reliable brand statistically speaking and it would live almost forever, or you could buy the more reliable brand/model statistically and it could die almost immediately. Those who pretend they can control such, or influence such are clearly fools themselves that are clearly wrong. Realty is that by the time word on the street leaks out and collects momentum the product line has changed and it's unreasonable to think that your results will be the same.
I'd point to the arguments I made a year ago as proof. A year ago OCZ was bashed heavily for reliability (they basically were the sole beta test program for Sandforce 22xx SSD controllers that had some growing pains.) but today it's pretty evident that they have improved. Vertex4 and Vector lines have very good reliability so far and data even suggests the VERTEX3 line has improved quite significantly. My point was always it's unreasonable to think 6 months or 12 months later a consumer would have the same experience.
WD drives are no different. There has been good and bad both. I've owned 7 total Green drives. 2TB and 3TB both EARS and EARX/Z. Without a doubt they are as a product line the least reliable drives I have ever owned. I am near 100% on RMA. I have only a single 2TB green that is original and never swapped out.
But I don't think every green drive is crap or that someone buying one today would be likely to have my experiences. I'm open to the idea my case is bad luck.
I do believe that GREEN WD drives make a pretty good choice for simple storage inside a traditional desktop or HTPC environment. That is what they are recommended and designed for by WD. They are 5400rpm, run cool and quiet and have a nice energy profile. That is the advantage and that advantage lends itself well to HTPC or basic desktop applications. The disadvantage is they are slower and have lower performance ( an acceptable advantage in many cases depending on intended usage) and also they have less warranty and some long term endurance concerns, particularly in 24/7 server/NAS/ and RAID applications that they are not recommended for.
So I think aside from NAS / SERVER/ RAID applications, or set ups that employ >5 HDD's WD GREEN drives are probaly a great choice provided they have a good price. The tough part today is RED offers a longer warranty, better reliability due to improved anti shock and vibration features and lack of aggressive head parking features, and typically sell for the same prices. I'm with you... for the same price or even just $10 more I think the RED is a better choice for the longer warranty alone. I'd take the warranty for $10 or less but I would not pay more than $10 for it. I'd probably go $20 more if my set up was a set up that RED was recommended for and GREEN was recomended against. For $25 or more I'd probably still roll the dice with GREEN for the $$ savings.
Personally I view GREEN drives as a dated product that could be improved. It's not 2010 anymore. The advantage they once had about heat/energy/noise has mostly evaporated. It's not like they really hold any significant advantage at that in todays HDD landscape. The RED line often tests out with both better performance and better energy profile. They have equally good heat, noise and energy characteristics. Even other MFG like Toshiba, Hitachi, Seagate have significantly improved their newest next generation lines. The 4TB seagate 5400rpm drives appear to be gaining momentum and considering you can buy a 4TB 5400 RPM Seagate drive for $150 they hold an advantage in price. They do use more energy than a GREEN drive (I think) but certainly less than 2 Green drives. After all they do hold 4TB versus 2TB so it's not a fair comparison.
My favorite drive right now is the 7200.14 3TB Seagates. They are $40 per GB (cheapest around) and offer increased performance at the same time. They are perfectly acceptable in heat and noise and energy being a next generation drive. They are a better choice in RAID, NAS or Server Set ups IMO. But I just installed a 3TB EARX WD green in my brother's MILO 03 case today so I guess I am not that biased
I think your original comments ring true and that all HDD's are good and bad- and there is no sense to be made from any of it at the consumer level. It's as much luck as anything else. Consumers should looks at the features that are important to them and decide based on value. I'm not sure there is any "bad" products on the market today. I just think the GREEN drives are 2010 and the reality is they don't really have as much advantage as they used to have. But they were a good product in 2010, so it's reasonable to think they are a decent product in 2013.